- #1
reyes117
- 1
- 0
A locomotive is accelerating at 1.6m/s^2.It passes through a 20m wide crossing in a time of 2.4s . After the locomotive leaves the crossing , how much time is required until its speed reaches 32m/s?
=== I am using the equation x= Vot + 1/2 at^2
This is what i did, but I am not sure about it. I just want to make sure my procedures are correct. I don't know if i moved the question around correctly.
x = Vot + (1/2)at^2
20 = Vo(2.4) + (1/2)(1.6)(2.4)^2
Vo = [20 - (1/2)(1.6)(2.4)^2]/2.4
Vo = 6.41 m/s, speed of locomotive when leaves the
crossing
t = (Vf - Vo)/a
t = (32 - 6.41)/1.6
t = 15.99 or 16 sec
-------------------------------------------------------------------------------------
I need help on this question as well. Some one told me to use this equation mgh = (1/2)mV^2...but i have never seen it before and my teacher didn't mention it. Is there any other equation i can use? the ones my teacher has gone over are V= Vo + at, x+ 1/2(Vo + V)t, x= Vot + 1/2at^2, V^2+ Vo^2 + 2ax
The greatest height reported for a jump into an airbag is 99.4 m by stuntman Dan Koto. In 1948 he jumped from rest from the top of the Vegas World Hotel and Casino. He struck the airbag at a speed of 39 m/s (88 mi/h). To assess the effects of air resistance, determine how fast he would have been traveling on impact had air resistance been absent.
***** Any help would be deeply appreciated! Thanks in advance!****
=== I am using the equation x= Vot + 1/2 at^2
This is what i did, but I am not sure about it. I just want to make sure my procedures are correct. I don't know if i moved the question around correctly.
x = Vot + (1/2)at^2
20 = Vo(2.4) + (1/2)(1.6)(2.4)^2
Vo = [20 - (1/2)(1.6)(2.4)^2]/2.4
Vo = 6.41 m/s, speed of locomotive when leaves the
crossing
t = (Vf - Vo)/a
t = (32 - 6.41)/1.6
t = 15.99 or 16 sec
-------------------------------------------------------------------------------------
I need help on this question as well. Some one told me to use this equation mgh = (1/2)mV^2...but i have never seen it before and my teacher didn't mention it. Is there any other equation i can use? the ones my teacher has gone over are V= Vo + at, x+ 1/2(Vo + V)t, x= Vot + 1/2at^2, V^2+ Vo^2 + 2ax
The greatest height reported for a jump into an airbag is 99.4 m by stuntman Dan Koto. In 1948 he jumped from rest from the top of the Vegas World Hotel and Casino. He struck the airbag at a speed of 39 m/s (88 mi/h). To assess the effects of air resistance, determine how fast he would have been traveling on impact had air resistance been absent.
***** Any help would be deeply appreciated! Thanks in advance!****